A bearing and navigation system for land vehicles is already known from German Published Patent Application DE-OS 35 12 127, Freienstein et al., by means of which it is possible to arrive at the destination in an optimal manner. If the position of the vehicle and the destination are known, the known navigation system will provide guidance to the destination in an optimal manner.
A further navigation system is known from German Published, Non-Examined Patent Application DE-OS 29 25 656 PILSAK, corresponding to U.S. application Ser. No. 159,485, filed Jun. 16, 1980, now abandoned. In this destination guidance system, data regarding the position of the bases in the terrain are transmitted to the vehicle by these bases. The travel route, which will lead to the destination, is selected by the navigation system on the basis of simultaneously transmitted possible routes.
Receivers for decoding traffic advisories are known, for example, from our German Published Patent Application DE-OS 35 36 820, Braegas & Busch/Bosch. The traffic advisories are digitally transmitted with the known radio traffic service decoder and are displayed visually or acoustically. In this connection, the traffic advisory is transmitted in a standard way, so that streets and routes as well as place names and the type of obstruction can be easily ascertained.
German Published Patent Application DE-OS 37 24 516, corresponding to U.S. Pat. No. 5,095,532, Mardus discloses and describes a method for a route-selective reproduction of traffic advisories, as well as an appropriate receiver in the vehicle, by means of which it is possible to issue only those traffic advisories which are applicable to a defined route. It is achieved, by means of this measure, that not every traffic advisory is issued, but only a limited number of traffic advisories which actually are of interest to the driver.
In known navigation systems, it is disadvantageous that the route is determined and issued without regard to traffic conditions. Although it is possible for the driver, for example in case of blocked streets, not to follow the suggested route and to take another direction instead, after which a new route is determined by the navigation system, obstructions are often not immediately apparent, for example if there is a tie-up or jam in the area of the suggested route.